Method

Go to Julius in the Trade Quarter and talk with him to start the quest.

For missions 6 to 10, if you do the quest "in one go", it could be helpful to have two friends keep clear the path from the boat on Vengoth to the entrance of the castle in the mountains, because you will have to walk this way about a dozen times and the monsters on the way could be really really annoying, depending on your level and walking speed.

Mission 03: His True Face

Julius wants you to cast the spell "alori mort" on the Suspected Vampire NPCs. Say hi, and while facing them directly say the spell. You need only go to Armenius, the head vampire. There's a small chance that Armenius show you his true face, and will teleport you to his basement. If this happens you will receive the achievement His True Face and face Armenius. This is a rare achievement which is supposedly obtainable through another method, but this is undiscovered.

Mission 04: The Dark Lands

Go to Harlow at the Trade Quarter docks and ask for passage to Vengoth. Search Vengoth for at least 5 strange spots and use Julius' Map to mark them. Julius requires the castle, but will accept any other 4. If you mark more than 5 spots then Julius will offer an experience reward for each additional spot, up to a maximum of 7500 experience for all 8. Marking all 8 is one of the requirements for the Castlemaniaachievement.

Mission 05: Into the Castle

This mission is split up into several smaller missions. The first one is to get a Blood Crystal. Julius tells you to ask around in Yalahar, this is how some NPCs respond to "blood crystal":

Player: blood crystal
Znozel: Oooooooooh shiny shiny shiny shiny!! Give me!!
Redward: Huh? I think my master had one. But I really don't feel like going back and checking this for you. Sorry!
Morpel: No, I don't sell that, sorry.
Serafin: This is a fruit store. No slaughterhouse.
Soilance: No, haven't heard about that.
Lisander: No, that's wine I'm drinking.
Pugwah: Big red crystal. Some people talk about it in my tavern. But strange people those are!
Karith: I'm not interested in stuff like that.
Captain Cookie: That doesn't sound really tasty.
Lorietta: Ehehehe! A blood crystal? You must be a fool looking for one. I like fools. Why don't you check the cultist hideout in the magician quarter?
Palimuth: What would you need a blood crystal for? Maybe a magician knows where to find one.
Timothy: Oh yes, I heard about a gem like that. Nowadays they seem incredibly hard to acquire. The explorer's society doesn't own one, else I'd help you.
Dorbin: I agree, that would be a nice decoration object. Unfortunately I don't sell them.
Oiriz: Haha, they are not meant to be owned by ordinary humans. Sorry, but no.
Gree Dee: If I had one, I could charge a fortune for it... <gets a dreamy look>
Chuckles: Oooh, you're playing with fire. <chuckles>
Vincent: What's that supposed to be? Anyway, I don't sell it.
Zarak: A true warrior doesssn't need jewellery.
Maris: No, thanks.
Tony: Sorry... but uhm... please move on, I actually shouldn't chat with you.
Hal: What the h... heck are you talking about?
Bruce: I have nothing to say about that topic.
Reed: It's nice talking to you, but honestly, you give me the creeps. So please decide what you want and move on.
Tamoril: If I had one, I'd surely add it to my treasure and not give it to you.
Tamara: Oh! That cursed stone! I know about it, but I can't tell you anything. Evil gems like that shouldn't be passed around, only a crazy fool would do that.
Ethan: Tamara mentioned it sometime ago.
Barry: This is of no importance to me right now.
Oliver: I'll tell you that story another time, but not now. Sorry.
Peter: Listen, I don't get paid enough to chat with citizens. Move on.
Armenius: If you want blood, go kill a pig.
Harlow: What the heck, stop bothering me with your questions.

Julius will tell you that you need to charge the crystal with the energy from someone who has lost everything. Go to the Wandering Soul on Vengoth and tell him "blood crystal". Now you have a charged crystal.

For this next part of the quest you need 4 people (total) who are on the same mission to continue. Make sure you have exactly 4 people on the same part otherwise you will have to wait until others reach this point in the quest. The blood crystal is charged only for the time being. You see it sparkling as long as it's charged. So in case you have to wait some longer to find the members for this part of the quest, you may need to recharge the crystal. For this just go back to the Wandering Soul, say "hi", "mission", "blood crystal" and you can continue with the quest.

Each of the 4 people will need their charged blood crystal for the next part of this mission. You must then find 4 strange carvings (which are partly buried), each player stands on one of the carvings. Two of them are on the ground floor, one near the castle and another near the poison shrine, right and left to the entry. As soon as the 4th member tapped onto his spot all will get teleported into the corridor of the castle. Inside you won't have to fear any monster. Once you have been there, go back to Julius and report your mission.

Mission 06: A Black History

Your next mission is to find any information on the castle. Enter the main hall and use the southern part of a small Old Carpet (Blue) in order to find a Closed Trapdoor. Use the trapdoor to open it and go down.

Once downstairs, head south. You will face the following creatures in chronological order:

After receiving the first part of the diary, Julius would like you to bring him any other missing diary pages you might find so that he can piece together the entire story. He will give you 1000 experience points for each of the six diary pages you can find hidden inside several containers throughout the castle. Doing this is not required in order to be able to complete the quest, but it is one of the requirements for the Castlemaniaachievement.

Proceed to the top of the tower if you wish to immediately obtain another part of Marziel's diary. You will face the following creatures in chronological order:

Mission 10: Arthei

In this mission you will kill the fourth and last of the vampire lord brothers, Arthei. Go into the Open Trapdoor in the hall again and go north again. You will face the following creatures in chronological order:

Transcripts

Mission 01: Gaining Trust

Player: HelloJulius: Be greeted, adventurer player. I assume you have read the note about the vampire threat in this city.Player: note/vampire
Julius: Our nightly blood-sucking visitors put the inhabitants of Yalahar in constant danger. The worst thing is that anyone in this city could be a vampire. Maybe an outsider like you could help us. Would you try?Player: yes
Julius: Well, there's one problem. How would I know I can trust you? You might be one of them... hm. Can you think of something really unlikely for a vampire? If you know a way to prove it to me, ask me about your mission.Player: mission
Julius: I fear that will not do. Sorry.

Julius: Be greeted, adventurer player.Player: mission
Julius: Hmm, I see, I see. That necklace is only a small indication though... I think I need another proof, just to make sure. Say... have you ever baked garlic bread?Player: no
Julius: Well, you need to mix flour with holy water and use that dough on garlic to create a special dough. Bake it like normal bread, but I guarantee that no vampire can eat that. Are you following me?Player: yes
Julius: Fine then. Talk to me again about your mission once you have the garlic bread. You can get holy water from a member of the inquisition.

Player: mission
Julius: Let me check - yes indeed, there's garlic in it. Now eat one, in front of my eyes. Right now! Say 'aaah' when you've chewed it all down so that I can see you're not hiding it!Player: aaah
Julius: Very well. I think I can trust you now. Sorry that I had to put you through this embarassing procedure, but I'm sure you understand. So, are you ready for your first real task?Player: yes
Julius: As I already told you, anyone in this city could really be a vampire, even the most unsuspicious citizen. I want you to find that brood. ...
Julius: You can possibly identify the vampires by using a trick with hidden garlic, but better put it into something unsuspicious, like... cookies maybe! ...
Julius: Just bake a few by using holy water on flour, then use that holy water dough on garlic, use the garlic dough on a baking tray and finally place the tray on an oven. Then just play little girl scout and distribute some cookies to the citizens. ...
Julius: Watch their reaction! If it's suspicious, write down the name and let me know. Then we'll work something out against them. Agreed?Player: yes
Julius: Fine. Good luck! Talk to me again about your mission once you have confirmed the names of five suspects.

Mission 02: Bad Eggs

Player: mission
Julius: Are you back with confirmed names of possible vampires?Player: yes
Julius: Alright, wait a moment. Tell me one name at a time so I can note them down carefully. Who is a suspect?Player: maris
Julius: He really doesn't look like the man of the sea he pretends to be, does he? Noted down! Any other name?Player: ortheus
Julius: I always thought that there is not really a poor beggar hidden under those ragged clothes. Noted down! Any other name?Player: serafin
Julius: Nice angelic name for a vampire. But he didn't escape your attention, well done. Noted down! Any other name?Player: lisander
Julius: Yes, that pale skin and those black eyes speak volumes. Noted down! Any other name?Player: armenius
Julius: Ahh, I always thought something was suspicious about him. Noted down! Any other name?Player: no
Julius: I guess Armenius, Lisander, Maris, Ortheus and Serafin are all the names we can get for now. Let me think for a moment what we are going to do, talk to me about your mission again later.

Player: mission
Julius: Listen, I thought of something. If we could somehow figure out who among those five is their leader and manage to defeat him, the others might give up too. ...
Julius: Without their leader they will at least be much weaker. Before I explain my plan, do you think you could do that?Player: yes
Julius: Great, now here's my plan. As I said, my strength lies not on the battlefield, but it's theory and knowledge. While you were distributing cookies I developed a spell. ...
Julius: This spell is designed to reveal the identity of the master vampire and force him to show his true face. It is even likely that it instantly defeats him. ...
Julius: I want you to go to the five vampires you detected and try out the magic formula on them. One of them - the oldest and most powerful - will react to it, I'm sure of it. The words are: 'Alori Mort'. Please repeat them.Player: alori mort
Julius: Good. Don't play around with the spell, only use it when standing in front of those vampires. Come back and report to me about your progress later.

Mission 03: His True Face

Player: alori mort
Lisander: Hold your tongue.

Player: alori mort
Maris: Stop mumbling and don't bug me.

Player: alori mort
Serafin: There's something about these words which makes me feel awkward. Or maybe it's you who causes that feeling. You better get lost.

Player: mission
Julius: Oh! You look horrible - I mean, rather weary. What happened? Who is the master vampire?Player: armenius
Julius: I see... so Armenius is the master, and the spell didn't even cause a scratch on him... Well, that went worse than expected. Let me think for a moment and then ask me about a mission again.

Mission 04: The Dark Lands

Player: mission
Julius: You know, I came to think that the spell didn't work because there is another, greater power behind all of this. I fear that if we don't find the source of the vampire threat we can't defeat them. ...
Julius: I heard that there is an island not far from here. Unholy and fearsome things are said to happen there, and maybe that means vampires are not far away. ...
Julius: I want you to try and convince someone with a boat to bring you to this island, Vengoth. I'll give you an empty map. Please map the area for me and pay special attention to unusual spots. ...
Julius: Mark them on my map and come back once you have found at least five remarkable places on Vengoth. Can you do that for me?Player: yes
Julius: Here is the map. When you are standing near a remarkable spot, use it to mark that spot on the map. Don't forget, come back with at least five marks! ...
Julius: Also, they say there is a castle on this island. That mark HAS to be included, it's far too important to leave it out. Good luck!

Player: mission
Julius: Are you back with a useful map of Vengoth?Player: yes
Julius: Well done, you even marked seven places! I'll grant you a little bonus for that. Come back later and ask me about your next mission. I have to think.

Mission 05: Into the Castle

Player: mission
Julius: The spots you found on Vengoth are really interesting, especially the castle. There's something dark and spooky surrounding all of these places. ...
Julius: I think if we found a way to get into the castle, we might get to the bottom of all this. Are you prepared to help me?Player: yes
Julius: Good, now listen to what I've thought of. From what I've heard, there's a strong magic barrier blocking the entrance to the castle. ...
Julius: If we could somehow redirect or focus that energy somewhere else, it might be possible to pass that door. I heard of a rare stone called 'blood crystal'. ...
Julius: It is said to have the power to store magic energy. If you could find such a stone we might be able to charge it with energy that will attract the dark power floating around the castle. ...
Julius: Unfortunately I have no idea where to look for a blood crystal. I think you might have to ask around in Yalahar, maybe someone knows where you could find one. Can you do that?Player: yes
Julius: Fine then. Good luck!

Player: mission
Julius: As I said, I don't know where you might get a blood crystal - but did you find one?
Player: yes
Julius: Oh, look how it shimmers... such a pretty sight... now we just need to get it filled with magic energy. Maybe if you could find someone ...Player: ... someone who lost something or someone dear to him or her. Sometimes those people unknowingly emit massive amounts of energy - during their life and even after their death. ...
Julius: If you can find someone like that, I'm sure that you will be able to charge the blood crystal. That's the only help I can give you though. Are you willing to try?Player: yes
Julius: Once you have a charged crystal, hurry back to me. I don't know how long that power will last. Good luck!

A Wandering Soul: I saw you... who are you... what do you want from me...?Player: blood crystal
A Wandering Soul: What the...? I don't know anything about that... still... the pain felt a little less intense for a second... relieving... but will never be gone.

Player: mission
Julius: Ah! I can see in your eyes that you found someone! Do you have that charged crystal?Player: yes
Julius: Very good, now don't lose that precious crystal! I doubt you'll be able to get another one. While you've been on the road, I wasn't lazy either. ...
Julius: I have good news and bad news. Which do you want to hear first?Player: yes
Julius: Well, in that case I'll tell you the good news first. I figured out how you can get into the castle using that blood crystal, quite easy actually. ...
Julius: The bad thing is, you can't do it alone, but you need three more people who are also in possession of a charged blood crystal. ...
Julius: The four of you have to stand on special spots around the castle. Unfortunately, in my books it doesn't say where exactly, but it mentions strange symbols. ...
Julius: Once all four of you are standing on those spots holding a crystal, each of you will attract the castle's dark energy and get attuned to it. ...
Julius: I don't know what will happen, but afterwards you should be able to pass the castle gate, if I'm not mistaken. Do you think you can do that?Player: yes
Julius: Great. You are impressing me more and more. Once you have been to the castle, come back and we will discuss further missions.

Mission 06: A Black History

Player: mission
Julius: Ah! Welcome back! So you have been inside the castle? Was it as spooky as in the stories told by people?
Player: yes
Julius: Well anyway, as it seems there's more than that door protecting the castle, since you were not able to proceed any further - and those ghosts patrolling the hallway seem invulnerable. ...
Julius: I wonder what the story behind this place is. Maybe you can somehow find a way past the ghosts and deeper down into the castle. ...
Julius: If you could find some documents or books about this place there that would be a great help. Anything that tells us more about the master of this castle and how this place got so cursed. Could you do that?Player: yes
Julius: Fine. You know, those old castle sometimes have hidden passages and stuff like that. That's at least what they say in fairytales. Good luck!

Player: mission
Julius: Did you find anything of interest inside the castle?Player: yes
Julius: Oh! That is indeed MOST interesting. Can I have that book you found?Player: yes
Julius: Thank you so much, I'll grant you a small bonus for that. Let me take a closer look, hmm. There are a lot of pages missing... but that last page is kind of disturbing. ...
Julius: The name on the front page says 'Marziel'... and it seems that his brothers and himself have something to do with this place. ...
Julius: There are a lot of missing pages... I wonder what happened after March 30th? Listen, should you stumble across any more pages, please bring them to me for a small reward. I'd really like to figure this out. ...
Julius: Apart from that, I guess to meet the brothers, you have to explore the castle even more. Maybe you can find another open door somewhere and look where - or who - it leads to?Player: yes
Julius: Good luck. I mean it.

Mission 07: Boreth

Player: Mission
Julius: Impressive. A plant-crazy vampire... didn't think something like that existed. Have you got proof of his death?Player: Yes
Julius: That's what I was hoping for! I will start investigating that dust. Maybe we can gain valuable information on how we can defeat the vampire plague once and for all. ...
Julius: Listen, brave vampire slayer, I don't think that your task in this castle is done yet. According to the diary you found, there are three other brothers called Lersatio, Marziel and Arthei. ...
Julius: We have to seek them all out and destroy them in order to weaken their power over the land. After Boreth's death, it is quite possible that you can gain access to another tower in the castle. ...
Julius: That is your chance to find the second brother and awaken him. Good luck - again.

Mission 08: Lersatio

Player: Mission
Julius: A vain vampire hoping to see his image in the mirror once again some day... how ironic. Have you got proof of his death?Player: Yes
Julius: You are definitely one of the bravest and craziest adventurers I ever met. Each time you prove to me that there is no task too dangerous for you. ...
Julius: There are only two brothers left now, and I can feel that their grasp on Yalahar is getting weaker. We cannot stop now but have to finish what we started. ...
Julius: See if you can slip into another tower of the castle and climb up to the room of the third brother. Since Arthei is their master, I guess Marziel is who we are going for now. ...
Julius: The author of that diary... writing down the cursed story of his life. I hope he will rest in peace. Good luck.

Mission 10: Arthei

Player: HiA Fading Memory: Ohh...Player: Kala
A Fading Memory: ... yes! That's my name... how come you know that?Player: diary
A Fading Memory: ... you... read Marziel's diary and know our story...?Player: yes
A Fading Memory: ... then... tell me... I'm so sad... was it my fault? Why did he leave me... Arthei..?Player: vampire
A Fading Memory: ... so there is nothing I could have done...? He's a vampire now... what can we do...Player: free soul
A Fading Memory: ... he can't be freed from his curse that easily... he must be awaken first...Player: awaken
A Fading Memory: ... to awake him... I don't know but... he once truly loved me... maybe there is still something left... somewhere... here... take this from me....and thank you for listening...